Solar panels and battery - any real world reccomendations?

Just had our first installer out to quote about an hour ago and this was one of our questions as well - can totally charge off peak (people are talking about it earlier in this thread) and run stuff during the day, but it will drain pretty damn rapidly!
 
GuruJockStrap said:
Silly question.

If you go for a solar panel and battery combo, could you technically program it to charge the battery during economy 7 period pulling from the grid and then when you wake up and start using appliances, power is drawn from the battery?

Given the size of a single battery unit, could that possibly get you through the day or would a couple of kettle boils, a washing machine cycle, tumble dryer cycle, etc drain it next to no time?
Click to expand...

Yes, the only risk however is with more people doing it, particularly as EVs get more common, your relying on your cheap night rate staying cheap, at the hands of the energy companies.
 
BUDFORCE said:
Yes, the only risk however is with more people doing it, particularly as EVs get more common, your relying on your cheap night rate staying cheap, at the hands of the energy companies.
Click to expand...

Yes that's correct, I originally looked at batteries only but thought what happens if the energy companies pull the plug ( or make less attractive) on cheap rates, I'd be stuffed so decided solar and batteries with the added benefit of cheap rates as and when.
 
GuruJockStrap said:
Silly question.

If you go for a solar panel and battery combo, could you technically program it to charge the battery during economy 7 period pulling from the grid and then when you wake up and start using appliances, power is drawn from the battery?

Given the size of a single battery unit, could that possibly get you through the day or would a couple of kettle boils, a washing machine cycle, tumble dryer cycle, etc drain it next to no time?
Click to expand...

Simply put, yes, but if you have a good Solar array you won't need to charge it overnight much and during the day power would be pulled firstly from the solar and then topped up with battery as required.

Single battery could get you through a day but you'll want solar to chug it along and help out with your base draw. if you used washing machine, tumble drier, dishwasher you'd go through it in a couple of hours, hence why you need to use appliances slightly more intelligently and staggered to ensure you're not going over the max discharge rate of your battery/solar and then having to use the grid. and as said above with the increase in EV's and people going on to cheaper night tarriffs I suspect the difference in rates will slowly decrease over the coming years.
 
anyone tried https://loop.homes/ - seem to allow you to pull your smart meter history in and then emulate the effects of solar. Don't have a smart meter yet so can't use it annoyingly....

One thing to remember is that a lot of the electricity usage isn't domestic: retail, offices, manufacturing etc draws a lot more during the day than the night so while batteries and electric cars may increase some of the night usage I doubt it'll change things that much. Whats more likely to change things is smart meter based surge charging.
 
Last edited:
SoliD said:
I've just gone for a 18x370w with 2x8.2 batteries for predicted 8 to 9000unit usage per year. (plans to move primary heating to air conditioning.) so hoping the solar can provide the majority of this cost.
Click to expand...

from your posts about improving insulation - analysing insulation and investing in that/mhrv may give better return, solar panels+batteries will drop further in price, too;
it's a bit like bev's becoming more economic as battery prices/economies of scale improve.
 
jpaul said:
from your posts about improving insulation - analysing insulation and investing in that/mhrv may give better return, solar panels+batteries will drop further in price, too;
it's a bit like bev's becoming more economic as battery prices/economies of scale improve.
Click to expand...

Definitely, the insulation thoughts came long before Solar as since we moved here 2.5 years ago, we only get a few months a year that i'd describe as comfortable (too hot/too cold + high humidity levels), but had other bits to do on the house first + covid delayed everything. Insulation should be about 1000 for all materials I wouldn't have needed to redecorate the rooms in the first place (celotex/wood/plasterboard etc). Stuff like Radiators etc I would have needed to replace as they're all originals from 1972 by the looks of the ones i've taken off. So if that reduces my heating cost by even just £100 per year then fantastic, but the fact i'll actually be comfortable all year round will pay for itself straight away.

Solar has only been a recent thing, and I think if I didn't have the aircon I would potentially have not bothered, but moving primarily to that as heat source it should reduce payback time significantly.
 
If people don't mind me asking and they have a 4/6kw system what kind of generation do you get per day in summer? Just wondering how worth it a battery might be as I would want it topped up via solar only if I could.

Also would you recommend anybody in the Essex area?
 
Last edited:
rodders said:
South coast, I can be around 25kwh on a 4kw system on a full sun day.
Click to expand...

Damn, thats pretty good, going by that battery would be advisable, sounds like if I could get a 6kw system and a battery for 10k or under that would be the sweet spot for us. 7 or 10kw battery would be nice but probably out of price range.

Wonder if these do any wiggle room on their pricing or drop that 10kw battery down a few lol

https://first4solar.co.uk/pv-and-battery/
 
Last edited:
Also doesn't power your appliances all evening in the winter when your solar isn't generating. Payback on batteries with off peak charging is pretty good even better with solar.
 
Ron-ski said:
Same here in Thanet, can get just over 25kwh on a 4kw system, best month for me was May 2019, average of 23kwh a day.
Click to expand...
Was that soon after fitting?
Solar panels degrade over time as batteries do, but a particularly sunny month would make up for it. Think the drop off is quite sharp initially and then slows.

Just started looking into solar and battery. My energy supplier gave an initial quote of £8950 for a 12 panel 4.32kWp system but that only includes a 2.6kwh battery for that price. Interest free payments for I think 3 or 4 years. Doesn't seem that great an offer and will look at getting other quotes. I know a few who have used some small local company and they've close up shop so aftersales support has been non existent so that's a benefit of using a larger energy supplier - hopefully won't go bust.

Are batteries okay in the loft? Someone mentioned they have the battery stored in the loft but I can imagine the temps getting pretty high up there during the summer months. Will it lead to a higher level of battery degradation?
 
My panels were fitted in December 2015, generation has been about the same each year, the app doesn't show pre 2018, 2021 was the worst at 4.15MWh, 2020 the best at 4.51MWh, which I think is 4510Kwh.

My loft gets very warm in the summer, I have the inverter in there, I don't have batteries at the moment, but if I did the only place they could really go is outside.
 
DarrenM343 said:
Solar panels degrade over time as batteries do, but a particularly sunny month would make up for it. Think the drop off is quite sharp initially and then slows.
Click to expand...

No they are nothing like batteries for fall of at all, they degrade incredibly slowly and in weather like we have in the UK that isn't very hot and very sunny they degrade even more slowly that if you were in California or Australia. That is why most (even cheap) panel manufacturers can give figures like 80% of output after 25-30 years, some are even pushing beyond that now.

DarrenM343 said:
My energy supplier gave an initial quote of £8950 for a 12 panel 4.32kWp system but that only includes a 2.6kwh battery for that price. Interest free payments for I think 3 or 4 years. Doesn't seem that great an offer and will look at getting other quotes.
Click to expand...

That is terrible, you can get 6kW+ system and 10kWh of batteries for ~£10k depending on secondary costs, like scaffold etc.

DarrenM343 said:
I know a few who have used some small local company and they've close up shop so aftersales support has been non existent so that's a benefit of using a larger energy supplier - hopefully won't go bust.
Click to expand...

Not sure why it matters too much the installer only needs to cover the workmanship warranty, so just make sure they have all the relevant insurances etc. and ask them to show you a previous job or two they have done recently. As for aftersales support, if you are buying something like a GivEnergy battery system they support it directly for technical, not physical issues, but once it is up and running it should be fine, and if you need to make a warranty claim that would be with them as well. From the solar side of things then it is even less trouble really, they are mostly fit and forget, and if you monitor your generation you can easily see if anything isn't working as intended.

DarrenM343 said:
Are batteries okay in the loft? Someone mentioned they have the battery stored in the loft but I can imagine the temps getting pretty high up there during the summer months. Will it lead to a higher level of battery degradation?
Click to expand...

Most home batteries are LiFePo4 and they work normally in 30-50c temps, the degradation would be no higher than it is fitted in the garage like mine are.
 
You must log in or register to reply here.
Back
Top Bottom